The skin in hypermobile Ehlers-Danlos syndrome
Dr Nigel Burrows, Consultant Dermatologist, Addenbrooke's Hospital, Cambridge
Please note: The following text cannot and should not replace advice from the patient's healthcare professional(s). Any person who experiences symptoms or feels that something may be wrong should seek individual, professional help for evaluation and/or treatment. This information is for guidance only and is not intended to provide individual medical advice.
The cutaneous (skin) hallmarks of the Ehlers-Danlos syndromes (EDS) are variable depending on the subtype. The skin changes in hypermobile EDS (hEDS) tend to be less pronounced than in classical EDS (cEDS) although they can overlap with the milder forms of cEDS.
The skin has a soft, velvety texture, but this is a subjective feature. It can be more easily appreciated on the forearms although the changes will be present at any site.
Affected children fall more easily due to poor joint and muscle control associated with joint laxity. Small atrophic (thinned) scars may follow trauma at sites such as the forehead, chin, elbows, knees and shins. However, significant or severe scarring is not a feature of hEDS.
Cutaneous stretchibility (hyperextensibility)
Cutaneous hyperextensibility refers to the ability to stretch the skin beyond the normal range. When the skin is stretched, upon release, it recoils back to its original shape as elasticity of the skin is retained. Like skin softness, hyperextensibility can be difficult to assess in infants because of the relative increase in subcutaneous fat.
It is most accurately assessed by gently pulling the skin at the volar (hairless) part of the forearm or wrist until resistance is met. It is best to avoid testing at the extensor (outside) surfaces of joints where there is often excess skin. If the skin can be stretched more than 1.5cm this indicates hyperextensibility.
Although skin hyperextensibility characterises all EDS types (except for vascular EDS (vEDS) which has noticeably translucent skin with visible veins) its presence and severity are very variable in hEDS.
Easy bruising, at sites of trauma, accompanies most forms of EDS including hEDS. This occurs due to an increased fragility of dermal blood capillaries and poor structural integrity of the skin rather than a clotting abnormality.
Other less common skin features
These small (less than 1cm) and soft skin-coloured lumps appear on the sides of the heel when standing and disappear when the foot is elevated. Although usually symptomless they can occasionally be painful. They can occur without EDS and are caused by reversible herniation of the underlying fat into the dermis.
Elastoma perforans serpiginosa (Meischer’s elastoma)
This uncommon rash characteristically forms in a circular pattern with raised rough edges and a clear centre. It is usually sited over the neck and ﬂexures. Microscopic examination shows extrusion of broken elastic fibres (from the dermis) through the epidermis. It is more common in vEDS but may occur in hEDS as well as other connective tissue conditions such as Marfan’s syndrome, pseudoxanthoma elasticum and osteogenesis imperfecta.
Insufficient response to local anaesthetic
The first publication to demonstrate that some individuals with EDS (particularly the hypermobile type) do not get an adequate response to local anaesthetics was published in 1990. Up to nearly 60% of individuals with hypermobility may notice a poorer response to local anaesthetic. It is not uncommon for affected individuals to require larger doses of anaesthetic which can take longer to start working. A small study showed that the problem is unlikely to be due to rapid dispersal of the anaesthetic in EDS skin and the reason for the failure of local anaesthetic is not yet known. Affected individuals do not have any problems with general anaesthetics.
Management of the skin
No specific treatment presently exists for EDS but precautionary measures will greatly lessen the chances of accidental trauma, scarring or bruising. Simple measures, such as covering sharp edges of furniture and making homes safe to prevent falls are easy to do. Protective padding against the skin is not usually required as the skin is not significantly fragile. It is important, however, to alert surgical practitioners to the diagnosis of hEDS prior to operations so that they can take this into consideration when planning and undertaking any surgery.
As for other types of EDS any wounds should be closed without tension, preferably in two layers. Deep stitches should be applied generously. Superficial stitches should be left in place twice as long as usual and additional fixation of adjacent skin with broad adhesive tape (steristrips) can help prevent stretching of the scar.
Peer reviewed by: Dr Hanadi Kazkaz, Consultant Rheumatologist, University College London Hospital
Date of last review: 01/04/2016